// SPDX-License-Identifier: GPL-2.0
/*
* crc32-mips.c - CRC32 and CRC32C using optional MIPSr6 instructions
*
* Module based on arm64/crypto/crc32-arm.c
*
* Copyright (C) 2014 Linaro Ltd <[email protected]>
* Copyright (C) 2018 MIPS Tech, LLC
*/
#include <linux/cpufeature.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/string.h>
#include <asm/mipsregs.h>
#include <asm/unaligned.h>
#include <crypto/internal/hash.h>
enum crc_op_size {
b, h, w, d,
};
enum crc_type {
crc32,
crc32c,
};
#ifndef TOOLCHAIN_SUPPORTS_CRC
#define _ASM_SET_CRC(OP, SZ, TYPE) \
_ASM_MACRO_3R(OP, rt, rs, rt2, \
".ifnc \\rt, \\rt2\n\t" \
".error \"invalid operands \\\"" #OP " \\rt,\\rs,\\rt2\\\"\"\n\t" \
".endif\n\t" \
_ASM_INSN_IF_MIPS(0x7c00000f | (__rt << 16) | (__rs << 21) | \
((SZ) << 6) | ((TYPE) << 8)) \
_ASM_INSN32_IF_MM(0x00000030 | (__rs << 16) | (__rt << 21) | \
((SZ) << 14) | ((TYPE) << 3)))
#define _ASM_UNSET_CRC(op, SZ, TYPE) ".purgem " #op "\n\t"
#else /* !TOOLCHAIN_SUPPORTS_CRC */
#define _ASM_SET_CRC(op, SZ, TYPE) ".set\tcrc\n\t"
#define _ASM_UNSET_CRC(op, SZ, TYPE)
#endif
#define __CRC32(crc, value, op, SZ, TYPE) \
do { \
__asm__ __volatile__( \
".set push\n\t" \
_ASM_SET_CRC(op, SZ, TYPE) \
#op " %0, %1, %0\n\t" \
_ASM_UNSET_CRC(op, SZ, TYPE) \
".set pop" \
: "+r" (crc) \
: "r" (value)); \
} while (0)
#define _CRC32_crc32b(crc, value) __CRC32(crc, value, crc32b, 0, 0)
#define _CRC32_crc32h(crc, value) __CRC32(crc, value, crc32h, 1, 0)
#define _CRC32_crc32w(crc, value) __CRC32(crc, value, crc32w, 2, 0)
#define _CRC32_crc32d(crc, value) __CRC32(crc, value, crc32d, 3, 0)
#define _CRC32_crc32cb(crc, value) __CRC32(crc, value, crc32cb, 0, 1)
#define _CRC32_crc32ch(crc, value) __CRC32(crc, value, crc32ch, 1, 1)
#define _CRC32_crc32cw(crc, value) __CRC32(crc, value, crc32cw, 2, 1)
#define _CRC32_crc32cd(crc, value) __CRC32(crc, value, crc32cd, 3, 1)
#define _CRC32(crc, value, size, op) \
_CRC32_##op##size(crc, value)
#define CRC32(crc, value, size) \
_CRC32(crc, value, size, crc32)
#define CRC32C(crc, value, size) \
_CRC32(crc, value, size, crc32c)
static u32 crc32_mips_le_hw(u32 crc_, const u8 *p, unsigned int len)
{
u32 crc = crc_;
#ifdef CONFIG_64BIT
while (len >= sizeof(u64)) {
u64 value = get_unaligned_le64(p);
CRC32(crc, value, d);
p += sizeof(u64);
len -= sizeof(u64);
}
if (len & sizeof(u32)) {
#else /* !CONFIG_64BIT */
while (len >= sizeof(u32)) {
#endif
u32 value = get_unaligned_le32(p);
CRC32(crc, value, w);
p += sizeof(u32);
len -= sizeof(u32);
}
if (len & sizeof(u16)) {
u16 value = get_unaligned_le16(p);
CRC32(crc, value, h);
p += sizeof(u16);
}
if (len & sizeof(u8)) {
u8 value = *p++;
CRC32(crc, value, b);
}
return crc;
}
static u32 crc32c_mips_le_hw(u32 crc_, const u8 *p, unsigned int len)
{
u32 crc = crc_;
#ifdef CONFIG_64BIT
while (len >= sizeof(u64)) {
u64 value = get_unaligned_le64(p);
CRC32C(crc, value, d);
p += sizeof(u64);
len -= sizeof(u64);
}
if (len & sizeof(u32)) {
#else /* !CONFIG_64BIT */
while (len >= sizeof(u32)) {
#endif
u32 value = get_unaligned_le32(p);
CRC32C(crc, value, w);
p += sizeof(u32);
len -= sizeof(u32);
}
if (len & sizeof(u16)) {
u16 value = get_unaligned_le16(p);
CRC32C(crc, value, h);
p += sizeof(u16);
}
if (len & sizeof(u8)) {
u8 value = *p++;
CRC32C(crc, value, b);
}
return crc;
}
#define CHKSUM_BLOCK_SIZE 1
#define CHKSUM_DIGEST_SIZE 4
struct chksum_ctx {
u32 key;
};
struct chksum_desc_ctx {
u32 crc;
};
static int chksum_init(struct shash_desc *desc)
{
struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
ctx->crc = mctx->key;
return 0;
}
/*
* Setting the seed allows arbitrary accumulators and flexible XOR policy
* If your algorithm starts with ~0, then XOR with ~0 before you set
* the seed.
*/
static int chksum_setkey(struct crypto_shash *tfm, const u8 *key,
unsigned int keylen)
{
struct chksum_ctx *mctx = crypto_shash_ctx(tfm);
if (keylen != sizeof(mctx->key))
return -EINVAL;
mctx->key = get_unaligned_le32(key);
return 0;
}
static int chksum_update(struct shash_desc *desc, const u8 *data,
unsigned int length)
{
struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
ctx->crc = crc32_mips_le_hw(ctx->crc, data, length);
return 0;
}
static int chksumc_update(struct shash_desc *desc, const u8 *data,
unsigned int length)
{
struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
ctx->crc = crc32c_mips_le_hw(ctx->crc, data, length);
return 0;
}
static int chksum_final(struct shash_desc *desc, u8 *out)
{
struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
put_unaligned_le32(ctx->crc, out);
return 0;
}
static int chksumc_final(struct shash_desc *desc, u8 *out)
{
struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
put_unaligned_le32(~ctx->crc, out);
return 0;
}
static int __chksum_finup(u32 crc, const u8 *data, unsigned int len, u8 *out)
{
put_unaligned_le32(crc32_mips_le_hw(crc, data, len), out);
return 0;
}
static int __chksumc_finup(u32 crc, const u8 *data, unsigned int len, u8 *out)
{
put_unaligned_le32(~crc32c_mips_le_hw(crc, data, len), out);
return 0;
}
static int chksum_finup(struct shash_desc *desc, const u8 *data,
unsigned int len, u8 *out)
{
struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
return __chksum_finup(ctx->crc, data, len, out);
}
static int chksumc_finup(struct shash_desc *desc, const u8 *data,
unsigned int len, u8 *out)
{
struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
return __chksumc_finup(ctx->crc, data, len, out);
}
static int chksum_digest(struct shash_desc *desc, const u8 *data,
unsigned int length, u8 *out)
{
struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
return __chksum_finup(mctx->key, data, length, out);
}
static int chksumc_digest(struct shash_desc *desc, const u8 *data,
unsigned int length, u8 *out)
{
struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
return __chksumc_finup(mctx->key, data, length, out);
}
static int chksum_cra_init(struct crypto_tfm *tfm)
{
struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);
mctx->key = ~0;
return 0;
}
static struct shash_alg crc32_alg = {
.digestsize = CHKSUM_DIGEST_SIZE,
.setkey = chksum_setkey,
.init = chksum_init,
.update = chksum_update,
.final = chksum_final,
.finup = chksum_finup,
.digest = chksum_digest,
.descsize = sizeof(struct chksum_desc_ctx),
.base = {
.cra_name = "crc32",
.cra_driver_name = "crc32-mips-hw",
.cra_priority = 300,
.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
.cra_blocksize = CHKSUM_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct chksum_ctx),
.cra_module = THIS_MODULE,
.cra_init = chksum_cra_init,
}
};
static struct shash_alg crc32c_alg = {
.digestsize = CHKSUM_DIGEST_SIZE,
.setkey = chksum_setkey,
.init = chksum_init,
.update = chksumc_update,
.final = chksumc_final,
.finup = chksumc_finup,
.digest = chksumc_digest,
.descsize = sizeof(struct chksum_desc_ctx),
.base = {
.cra_name = "crc32c",
.cra_driver_name = "crc32c-mips-hw",
.cra_priority = 300,
.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
.cra_blocksize = CHKSUM_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct chksum_ctx),
.cra_module = THIS_MODULE,
.cra_init = chksum_cra_init,
}
};
static int __init crc32_mod_init(void)
{
int err;
err = crypto_register_shash(&crc32_alg);
if (err)
return err;
err = crypto_register_shash(&crc32c_alg);
if (err) {
crypto_unregister_shash(&crc32_alg);
return err;
}
return 0;
}
static void __exit crc32_mod_exit(void)
{
crypto_unregister_shash(&crc32_alg);
crypto_unregister_shash(&crc32c_alg);
}
MODULE_AUTHOR("Marcin Nowakowski <[email protected]");
MODULE_DESCRIPTION("CRC32 and CRC32C using optional MIPS instructions");
MODULE_LICENSE("GPL v2");
module_cpu_feature_match(MIPS_CRC32, crc32_mod_init);
module_exit(crc32_mod_exit);